Stationary induction apparatus



Jan. 2 1924. 1,481,904

A. B. HENDRICKS. 'JR

, STATIONARY INDUCTION APPARATUS Filed A=1z.2 1921 4 Inventor: 'AHan BHendricksJrt,

y 3}) (I V351 J H i S Attorney Patented Jan. 29, 1924.

umrso STATES B. HENDRICKS, JB., PITTSFIELD,

IASSACHUSETTB, ABBIGNOR TO GENERAL ELEc'rmo comm, a ooxroaa'rron or new Yoax.

STATIONARY mnuc'rzolt arrana'rtrs. Application am August a, 1921. Serial l lo. cause.

Towllwhomz'tmayconcem: Be it known that I. ALLAN B. Hanmuqxs, Jr., a citizen of the United States, residing at Pittsfield, county of Berkshire, State of Massachusetts, have invented certain new and useful Improvements in Stationary Induction Apparatus. of which the following is a specification.

y invention relates to stationary induction apparatus and has for its general object an improved construction and arrangement.

of parts.

' More particularly apparatus of this ty 0 16 high voltage service; for example m the z-servieerequired when it is desired to transform from one high voltage to' another as for instance where a tie-in transformer is required.

In desi ing apparatus of this character it is very ditlicult to place the rimary and secondary transformer windings in sulficiently close inductive relation to reduce the reactance to a satisfactory low value on account of the lar electrical clearances required between t e primary and secondary windings for insulating PUI'POSBS.'

In the practice of my invention I am able to accomplish the desired reduction in the reactance in such transformers by kee ing the primary and secondary win mgs grouped together but separate from one another, by disposing them on separate parts of e same core and coupling them magnetically or inductively by means of a third win ing which I have here styled a coupling tertiary.

or a more complete the nature and objects of my invention reference should be had to the following detailed description when taken in connection with the accompanyin drawing in which: F i'g. 1 shows, part y in elevation and partly in section, a transformer constructed m accordance with m invention; while Fig. 2 is an explanatory diagram.

ferring now to the drawing and particularly to F1 1, 1O denotes a magnetic core of the thr egged shell type, about the central or winding leg 11 of which are disposed the windings. Here the grou 12 will be considered the primary mg or that which receives energy from the supply circuit, while the lower group my invention relates to understanding of to 15 which of turns pe which is designed for.

sequently a 13 may be similarly considered the secondany or the one which supplies energy to the circuit fed by the trans ormer.

The coupling tertiary winding is shown .at 15, and comprises the two sections 15" and are arranged in close inductive relation with the primary and secondar windings 12 and 13 respectively. Thesections 15 and 15" are provided with the same number and are connected by conductors 16 in opposition to each other so that when the voltages induced therein are equal no circulatlng current flows through them. The sections 15 and 15" act to neutralize the leakage fluxes of the main and secondary windings 12 and 13 so as to maintain the same amount of main flux through both the primary and sedondarywindings. Since the secondary leak e flux tends to decrease the amount of main flux linking the secondary winding, the voltage induced in the section 15 of the tertiary coupling winding 15 is less than that indu' d in the section 15concircul ting current will flow through the two ctzons of the tertiary winding which will tend to neutralize the reducing the reactance between and secondary windin'gs.

If so desired an independent circuit 17 may be connected to the connection between the two sections 15 and 15" so as to supply power thereto or receive power therefrom.

Vith reference to this independent circuit the sections are connected in parallel whereas when they are considered by themselves they are connected in series and in opposition to each other. In this way three indeent circuits 17, 18 and 19 may be tied irogether by one transformer as indicated in The operation of my invention will be more clearly understood from a consideration of Fig. 2.

Here P denotes the primary, S the secolfidary, and a and 6 their respective sections 0 t connected in series. As a result the E. M. F .s, whose directions hese windings are symbolically indicated one respectively, I be related to each other as though two transformers were connected in cascade transformation for the windings P and Sr the primary and secondary windings in one relation; i. e. the E. M. F. in the section at a is opposed to that in the winding at P; and again the induced E. M. F. at a. produces, as a consequence of the tertiary current which flows, an equal and opposite and made as large as is desired in order to secure as close coupling magnetically bet 'een them and the tertiary as may be feasi b e. Such an arrangement is uivalent to connecting the windings P and in cascade by nieans of step-down and step-up transformers, I It is perceived, however, that to couple transformer, as I have described, very great-.

ly reduces the cost of the necessary appara-' tus and at the same time provides means for suppressing the leakage flux in a manner such that mechanically the windings may not be closely related but in effect magneticall they are closely coupled.

While I have shown and described my invention in connection with a single phase shell ty e transformer it is obvious to one skilled in the art thatmy invention is up plicable to other types of transformers such as 1polyphase and core type transformers.

aving now described an embodiment of my invention which is at present the best means known to me ior carrying the same into eliect, I would have it understood that this is merely illustrative and that do not mean to be limited thereby to the precise details shown nor iestricted in the choice of memos recognized equivalents except as defined in my claims hereunto annexe What I claim as new and desire to secure by Letters Patent of the United States, is

1. In stationarinduction apparatus, the combination, wit a. core, of primary and secondary windings disposed ively on separate portions thereof, and a tertiary-- coupling winding coupled closely ma etically with both said primary and semi secondaiiy.

2. a stationary inductionapparatus, the combination with a. core, of primary and secondary windings disposedv respectively on separate portions thereof, a'nd' a tertiary coupling windin composedof sections associatcd respective y with said'primary and said secondary and coupled closely magnetis cally therewith. I

3. In stationary induction apparatus, the combination with a core, of..primaryand secondary windings disposed 'frespectitely on separate portions thereof, andsections with said p'rimary andsaid secondary, said sections being connected in series and closely of a third winding associated respectively coupled magnetically with their respective 3o windings.

. 4.111 stationary induction apparatus. the combination witha core, of primary and secondary windings disposed rei-ipectively on separate portions thereof ,'and sections of a third windingdisposed along the core so as substantially to envelop the same magneticiated winding,

cally, said sections being associated res -1 tively with said primary and 'secon ar' In witness wheredf, I have hereunto set my hand this 29th do. of Jul 1921.

ALLAN ndianofiioxs, .n. 

